Infrared receptors in the facial pits of the Australian python Morelia spilotes

There is a series of pits in the scales of the rostrum and posterior portion of the lower lips in some pythons and boas. In the Australian python Morelia spilotes, these pits are innervated by the maxillary and mandibular branches of the trigeminal nerve. Structural and neurophysiological evidence indicate that in the pits there are receptors that function as detectors of radiant heat flux.     

蟒蛇性别鉴定技术

[目的]探索蟒蛇性别鉴定方法,为生产实践和蟒蛇研究提供理论基础。[方法]采用形态学观察和性别鉴定针法对111条不同年龄（1岁、2岁和3岁龄以上）缅甸蟒进行鉴定,记录其形态特征和性别鉴定针插入生殖腔部分所占的鳞片数,然后解剖查看其生殖器官验证其性别,统计雌雄蟒蛇的性别规律。[结果]雄性蟒蛇,进入生殖孔的鉴定针长度大部分占10～17片尾部鳞片,个别的占8、9和19片;而雌性蟒蛇,进入生殖孔的鉴定针的长度占到尾部鳞片的4～5片,相对比较集中。[结论]形态学观察和性别鉴定针鉴定法相结合可以方便、高效地判定出蟒蛇的性别。     

蟒蛇肺炎克雷伯氏菌的分离与鉴定

亚洲岩蟒主要栖息在热带与亚热带森林,具有较高的药物、营养和经济价值,人工养殖中常因肺炎而死亡.为调查该病病因,对海南省养殖场发病蟒蛇进行心脏穿刺采集血样、细菌培养、革兰氏染色镜检、16S rRNA基因序列测定和BLAST分析等方法寻找病原,结果表明,分离菌株为肺炎克雷伯氏菌.     

婴儿配方乳中n-3系多不饱和脂肪酸的研究

近年来的研究表明,n-3系多不饱和脂肪酸(n-3Polyunsaturotted Fatty Acids)具有防治心血管疾病、促进脑组织及视网膜的正常生长发育等生理功能和保健作用,因此越来越引起人们的关注。目前,在婴儿配方乳中n-3系多不饱和脂肪酸的应用越来越受到世界各国的重视。如何考虑n-3系多不饱和脂肪酸的平衡和摄取量,以充分发挥其对人体健康有益的作用,确保婴儿安全有效地利用n-3系多不饱和脂肪酸是值得注意的问题。     

三种根系分泌脂肪酸对花生生长和土壤酶活性的影响

为了探讨花生连作后土壤中脂肪酸类物质的累积与花生连作障碍间的关系,为花生连作障碍机理的研究提供新的理论依据,以田间土壤为介质,采用盆栽试验的方法研究了花生根系分泌物中3种长链脂肪酸,即:豆蔻酸、软脂酸和硬脂酸的混合物,对花生植株生长、产量和土壤酶活性的影响。结果表明,当土壤中脂肪酸的初始含量较低时(80 mg/kg土),对花生植株的生长和产量有微弱的促进作用(P > 0.05),当土壤中脂肪酸的初始含量较高时(160 mg/kg土和240 mg/kg土),显著抑制了花生植株的生长和产量(P < 0.05)。叶片叶绿素含量、根系活力、土壤酶(蔗糖酶、脲酶、磷酸酶)活性在低脂肪酸含量处理下升高,在高脂肪酸含量处理下显著降低(P < 0.001)。光合产物、根际有效养分的减少和根系养分吸收能力的降低,可能是导致花生植株生长和产量降低的原因之一。花生连作土壤中豆蔻酸、软脂酸和硬脂酸的累积与花生的连作障碍有着密切关系。     

Synaptic reorganization in the hippocampus induced by abnormal functional activity

Abnormal functional activity induces long-lasting physiological alterations in neural pathways that may play a role in the development of epilepsy. The cellular mechanisms of these alterations are not well understood. One hypothesis is that abnormal activity causes structural reorganization of neural pathways and promotes epileptogenesis. This report provides morphological evidence that synchronous perforant path activation and kindling of limbic pathways induce axonal growth and synaptic reorganization in the hippocampus, in the absence of overt morphological damage. The results show a previously unrecognized anatomic plasticity associated with synchronous activity and development of epileptic seizures in neural pathways.     

Thermoregulation in a brooding female Indian python, Python molurus bivittatus

At varying environmental temperatures, measurements of body temperatures and gas exchange of a female Indian python (Python molurus bivittatus) show that during the brooding period this animal can regulate its body temperature by physiological means analogous to those in endotherms. Ambient temperatures below 33 degrees C result in spasmodic contractions of the body musculature with a consequent increase in metabolism and body temperature.     

植物种子中脂肪酸代谢调控基因工程研究

脂肪酸代谢是植物最重要的代谢途径之一,脂肪酸在食用和工业生产上有重要用途。介绍了植物种子中脂肪酸代谢的基本途径。论述了应用基因工程改良植物种子油品质的技术策略、存在问题,同时对植物脂肪酸调控基因工程发展提出了展望。     

ω-3不饱和脂肪酸的生物学作用

由于人们的膳食中饱和脂肪酸 /多不饱和脂肪酸 (S/P)及 ω- 6不饱和脂肪酸 /ω- 3不饱和脂肪酸的比例失调 ,使得心血管的发病率显著增加。正因为 ω- 3不饱和脂肪酸的摄入量相对不足 ,所以人们更加重视ω- 3不饱和脂肪酸在脂肪酸促进胎儿和新生儿的大脑发育 ,抗肿瘤和炎性反应及降低冠心病、高血压、动脉粥样硬化、二型糖尿病等发病率的特殊作用 ,这些作用源于ω- 3的某些生物学作用。本文阐述 ω- 3功能活性的生物学作用基础     

Change in the fatty acid composition and physicochemical properties of pig back fat depending on growth rate

It is established that the content of saturated fatty acids increases and that of monounsaturated decreases with increase of growth rate at the finishing stage. The content of polyunsaturated fatty acids is related to growth rate to a lesser degree. The content of water in fat and refractive index decrease with its increase in the first fattening stage. An insignificant increase in high meltability of fat with increase of growth rate in the finishing stage is noted.     

Understanding changes in volatile compounds and fatty acids of Jincheng orange peel oil at different growth stages using GC–MS

Jincheng orange (Citrus sinensis Osbeck) is widely grown in Chongqing, China, and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds. The changes in aroma during the development and maturation of fruit are indicators for ripening and harvest time. However, the influence of growth stages on the volatile compounds in Jincheng orange remains unclear. In addition, volatiles originate from fatty acids, most of which are the precursors of volatile substances. On this basis, gas chromatography–mass spectrometry (GC–MS) was performed to elaborate the changes in volatile constituents and fatty acids as precursors. This study tested proximately 60 volatiles and 8 fatty acids at 9 growth and development stages (AF1–AF9). Of those compounds, more than 92.00% of total volatiles and 87.50% of fatty acids were terpenoid and saturated fatty acids, respectively. As shown in the PCA plot, the AF5, AF6, and AF9 stages were confirmed as completely segregated and appeared different. In addition, most of the volatiles and fatty acids first increased at the beginning of the development stage, then decreased from the AF6 development stage, and finally increased at the AF9 maturity stage. Moreover, the highest contents of terpenoid, alcohols, aldehydes, ketones, and saturated fatty acids in Jincheng orange peel oil were d-limonene, linalool, octanal, cyclohexanone, and stearic acid during development stages, respectively. Our results found that the growth stages significantly affected the volatile constituents and precursors in Jincheng orange peel oil.     

L-肉碱在猪生产中的应用

L-肉碱是一种类维生素制品,主要功能是参与动物体内脂肪酸代谢,作为载体将长链脂肪酸从线粒体膜外输送到膜内促进脂肪酸的β-氧化,将脂肪酸氧化并释放能量。L-肉碱也可以作为饲料添加剂,可提高动物的生产性能和瘦肉率,并降低脂肪含量,改善肉质,其应用前景十分广阔。文章就L-肉碱的特性、生理功能及其在猪生产中的研究作以综述。     

十字花科植物蜡质形成特性及分子机制研究进展

十字花科Brassicaceae包含蔬菜、油料作物、药用植物、观赏植物和染料植物等,是一类1年生、2年生或多年生的植物,是中国最重要的蔬菜和油料作物之一。蜡质的主要成分是超长链脂肪酸及其衍生物,十字花科植物的蜡质是其适应外界环境变化而形成的保护结构,在维持水分平衡、反射紫外线、减少外来机械损伤、降低低温伤害、抵御细菌真菌入侵、防止果实开裂与昆虫侵食等抵抗生物与非生物胁迫中起着重要作用。对十字花科植物蜡质类型、生理功能、遗传特性、合成与转运途径等方面进行综述,可为十字花科植物的蜡质代谢研究提供参考。图2表2参61     

脂肪酸对大巴山多脂鳞伞菌丝体生长的影响

用平板培养法研究了不同饱和度脂肪酸及其复配液对大巴山多脂鳞伞菌丝体生长的影响。结果表明:不同饱和度脂肪酸及其复配对多脂鳞伞菌丝体生长的促进作用不同;单不饱和脂肪酸+多不饱和脂肪酸对菌丝体生长的促进作用最大,菌丝体浓密、淡黄色,轮纹明显;饱和脂肪酸的促进作用最小,菌丝体较浓密,乳白色,轮纹不明显。     

Cell growth with trans fatty acids is affected by adenosine 3',5'-monophosphate and membrane fluidity

Two positional isomers (9 and 11) of trans octadecenoates did not support growth on glucose of an Escherichia coli mutant that requires unsaturated fatty acids. However, the trans fatty acids provided sufficient fluidity to produce much higher cell yields when the concentration of adenosine 3',5'-monophosphate was raised. The effectiveness of the trans acids rose from 0 to 1 cell per femtomole to 15 to 20 cells per femtomole as the concentration of adenosine 3',5'-monophosphate was increased. The corresponding cis positional isomers supported high yields (35 to 40 cells per femtomole) independent of supplementation. The enhanced growth with adenosine 3',5'-monophosphate supplementation is not due to an increased uptake and incorporation of the trans isomers relative to the cis isomers, since the 9-trans isomer was incorporated more rapidly than the 9-cis isomer into the membrane phospholipids under all growth conditions and represented 21 +/- 2 mole percent of the acids. The finding that cells growing with trans fatty acid isomers have a higher requirement for adenosine 3',5'-monophosphate may indicate that some fatty acids can alter the metabolic regulation normally exerted by the cyclic nucleotide.     

微藻脂肪酸合成累积代谢基因调控的研究进展

随着环境与能源问题的日益紧张,微藻成为生物柴油的重要原料,并且成为研究者们关注的热点。首先介绍了微藻作为生物柴油原料的优势,如生长速度快、生物量大、油脂含量多等。其次综述了关于微藻代谢途径的研究进展,分别从脂肪酸的合成和分解途径综述了人们近些年来对关键限速酶的研究进展,总结了不同限速酶取得的成果。提出采用基因沉默等方法来抑制脂肪酸的分解代谢。最后对微藻作为生物柴油原料的前景做了展望,目前已有乙酰辅酶A羧化酶(ACCase)等酶被研究,但还有脂肪酸合成酶(FAS)等酶以及其他旁路途经的相关酶有待于更深入地开发和研究。     

Artificial neural network models of the rumen fermentation pattern in dairy cattle

The objectives of this study were: (1) to predict the rumen fermentation pattern from milk fatty acids using a machine learning technique, i.e. artificial neural networks (ANN) combined with feature selection and (2) to compare the prediction accuracy of the resulting model to that of a statistical multi-linear regression model, based on odd and branched chain milk fatty acids. Data were collected from 10 experiments with rumen fistulated dairy cows, resulting in a dataset of 138 observations. Feature selection was based on correlation and principal component analysis, and background physiological knowledge. Different ANN architectures and training algorithms were assessed. The evaluation of the model performance, based on the test dataset, showed a root mean square prediction error, expressed relative to the observed mean, of 2.65%, 7.67% and 7.61% of the observed mean for acetate, propionate and butyrate, respectively. Compared to a multi-linear regression model, the ANN revealed not to perform significantly better. However, the results confirm that milk fatty acids have great potential to predict molar proportions of individual volatile fatty acids in the rumen.     

雌性阿根廷滑柔鱼性腺发育阶段的脂肪酸组成及其变化

阿根廷滑柔鱼是典型的头足类,资源生物量与其生长发育过程中营养物质积累及生殖投入密切相关。为了获知雌性阿根廷滑柔鱼性腺发育各阶段的脂肪酸组成及其变化特点,研究采用氯仿甲醇法和气相色谱法检测分析胴体、消化腺和卵巢的脂肪酸种类及其含量。结果表明,雌性阿根廷滑柔鱼胴体、消化腺和卵巢3个组织的脂肪酸均以多不饱和脂肪酸(PUFA)为主,饱和脂肪酸(SFA)次之,单不饱和脂肪酸(MUFA)的总含量最低。胴体组织的脂肪酸种类最全面,共检测出28种脂肪酸,消化腺和卵巢分别检测出21种和17种脂肪酸。检测发现3个组织中SFA均以C16∶0脂肪酸最为丰富,MUFA以C18∶1n9c和C20∶1脂肪酸为主,PUFA的DHA(C22∶6n3)最丰富,EPA(C20∶5n3)次之。胴体的SFA和MUFA在成熟期达到最大值,在产卵期显著降低;消化腺的PUFA保持相对稳定水平,但是其含量显著低于胴体和卵巢;卵巢持续积累脂肪酸,在产卵期时MUFA和PUFA显著降低。研究表明,雌性阿根廷滑柔鱼胴体、消化腺和性腺3个组织的脂肪酸种类具有组织特殊性,而主要脂肪酸具有一致性。性腺发育过程中,胴体的SFA和MUFA可能转化为能量供给卵巢发育,消化腺的PUFA则向胴体和卵巢转移,卵巢则持续积累脂肪酸供给卵子发生。